Multifunctional electrosurgical apparatus

CROSS-REFERENCE TO RELATED APPLICATION

0001This application is a continuation-in-part of U.S. application Ser. No. 10/853,126, filed May 26, 2004.

TECHNICAL FIELD

0002The present invention relates to electrosurgical devices and more particularly to devices used to deliver high or radio frequency electrical current to a target area in a body.

BACKGROUND OF THE INVENTION

0003Electrosurgical procedures typically rely on the application of high frequency, for example radio frequency (RF), energy to treat, cut, ablate or coagulate tissue structures such as, for example, neural tissue. One example of a treatment procedure incorporating the application of RF energy to treat neural tissue is lumbar facet denervation. The efficacy of the minimally invasive technique of delivering RF electrical current to neural tissue in lumbar facet denervation has been studied at length and these studies show that this procedure is an effective method of relieving low back pain. The high frequency energy is often delivered to a region of tissue from an energy source such as a generator via a probe that is inserted into a patient's body through an introducer needle. The resistance of tissue, located proximate a conductive region of the probe, to the high frequency energy, causes the tissue temperature to rise. The temperature is generally increased to a sufficient level to coagulate unmyelinated nerve structures, at which point a lesion is formed, resulting in pain relief. The probe is typically a stainless steel electrode that is manufactured to fit within an introducer needle (which may also be referred to as a cannula or tube). Some probes incorporate a temperature sensor to allow for monitoring of temperature throughout the procedure. The temperature can be used to control the delivery of the high frequency energy.

0004Introducer needles with varying geometries are used in such applications. For example, a tip of the introducer needle can be pointed, blunt and rounded, or open, varying in shape in accordance with the needs of different procedures. Pointed tips allow for penetration of tissue without the need for an external device while rounded tips are useful in soft tissue areas such as the brain where it is critical not to damage nerves. However, it should be noted that blunt introducer needles can do more tissue damage than small-diameter sharp introducer needles. U.S. Pat. No. 6,146,380 to Racz et al. describes introducer needles with curved conductive tips used in high frequency lesioning procedures. An introducer needle typically includes an insulated shaft with an electrically exposed and conductive tip at the distal end of the introducer. A hub at the proximal end of the introducer can also be provided as a connection site for an injection syringe. Introducer needles can therefore be used to inject anesthetic fluid or other treatment compositions, such as therapeutic agents, in addition to playing a role in the insertion of a device into a patient's body and the delivery of electrical energy to a region of tissue.

0005A typical treatment procedure utilizes an introducer needle having a hollow shaft and a removable stylet therein. This introducer needle is inserted into the patient's body and positioned via imaging technology. Once the introducer needle is positioned, the stylet is withdrawn. The distal end of the probe is then inserted into the shaft of the introducer needle until the distal end of the probe is at least flush with the distal end of the shaft. The probe is connected to a generator that generates electrical current. To ensure that only certain nerves will be treated, a stimulation procedure may be employed. This stimulation involves the delivery of low frequency electrical current in order to excite nerves. This procedure can differentiate between motor and sensory nerves and can confirm that the nerve to be treated is in fact the source of pain.

0006After placement is confirmed with the stimulation procedure, the probe is withdrawn. A syringe is then attached to the proximal end hub of the introducer needle in order to inject anesthetic fluid or other treatment compositions into the tissue. Following this injection of material, the syringe is removed and the probe is reinserted into the shaft of the introducer needle. Finally, high frequency electrical current is applied from the generator, via the probe and introducer needle, to the tissue adjacent the conductive tip and a lesion is formed. This high frequency electrical current generally returns to the generator through a return (also known as dispersive) electrode typically placed on an exterior surface of the patient's body.

0007Such a procedure can be used to denervate (that is, to neutralize the ability of neural tissue to convey signals to a patient's brain) specific portions of a patient's spine. Similar procedures may also be applied to other anatomical areas such as intercostal and trigeminal nerves. Accurate placement of the introducer needle's conductive tip in a complicated structure like the spine requires great technical skill by the treating physician. In these procedures, the introducer needle is often viewed via X-ray fluoroscopy, which assists in visualizing the introducer as it's guided into the patient's body.

0008One limitation of this technique is that placement achieved at the beginning of a procedure can be unintentionally altered by the attachment of a fluid delivery mechanism, for example a syringe, the actuation of the fluid delivery mechanism, or the removal and re-insertion of the probe after the stimulation procedure is complete. For example, to ensure that the fluid being injected does not leak, the fluid delivery mechanism must be tightly secured to the hub of the introducer needle. This twisting or pushing motion applies pressure to the introducer needle thus altering its placement within the body. Also, the probes are generally designed in such a manner that they are only slightly smaller than the inner diameter of the introducer needle to allow for a good electrical connection between the probe and the conductive tip region of the introducer needle. This tight fit requires the application of relatively high insertion forces to align the distal end of the probe with the end of the introducer needle. Therefore when the probe is inserted, removed or reinserted after the injection of a treatment composition, the forces applied can move the introducer needle. Movement caused by any of these inherent procedural complications creates a potential for unpredictable lesion development due to possible repositioning of the probes. The range of distance within which the tip of the introducer needle may move (thus altering the position of the probe) depends on the depth of the needle and the properties of the tissue. The tip may move radially up to 5 mm and axially up to 10 mm. Even slight variations in position can affect the outcome of the procedure. Therefore, placement often relies on the physician to visually monitor the position of the conductive tip throughout the procedure. However, variations in position can be so slight as to go unnoticed by a physician using the imaging technology currently available. Repeating the stimulation procedure to confirm the position of the probe following reinsertion is not viable since anesthetic has already been introduced. Thus, it would be beneficial to have a device or apparatus that would reduce or eliminate the need for those procedural steps that may result in unintentional movement of the introducer needle or probe.

0009Thus, based on the current state of the art, a need generally exists for an electrosurgical device or apparatus capable of overcoming some or all of the limitations and deficiencies of the prior art.

SUMMARY OF THE INVENTION

0010The present invention provides an electrosurgical apparatus with improved positioning characteristics. According to one broad aspect of the invention, an electrosurgical apparatus is provided for treating tissue. The apparatus comprises: an elongate shaft having a proximal region, a distal region, which comprises a conductive region, and one or more lumens therethrough; one or more apertures defined by the shaft and in communication with at least one lumen; a stylet occluding at least a portion of an opening defined by a distal end of the elongate shaft; an electrical coupling associated with the proximal region for flexibly coupling to a power source for supplying energy to the conductive region; a temperature sensor associated with the distal region; and at least one fluid delivery interface connection flexibly coupled to the proximal region for coupling a fluid delivery mechanism to deliver a treatment composition through at least one of the apertures.

0011In some embodiments of the invention, the temperature sensor is a thermocouple, and the thermocouple may include one or more of the conductive region and the stylet as its components. In certain embodiments, the stylet may be attached to the shaft of the apparatus. Some embodiments comprise one or more apertures located on a side of the shaft, with smooth walls for minimizing trauma to bodily tissue. Further possible features of the apparatus include one or more markers, including, for example, radiopaque markers and orientation markers. In addition, one or more of the shaft lumens may house wiring for connecting the conductive region to the energy source or for transmitting temperature measurements. Another possible feature that may be included in the apparatus is a handle associated with the proximal region of the shaft. The handle may include one or more markings, for example orientation markings, a strain relief and/or a grip.

0012As a second broad aspect of the invention, an electrosurgical apparatus is provided for treating tissue. The apparatus comprises: an elongate shaft having a proximal region, a distal region, which comprises a conductive region, and one or more lumens therethrough; one or more apertures defined by the shaft and in communication with at least one lumen; an occluding means occluding at least a portion of an opening defined by a distal end of the elongate shaft, where the occluding means is attached to the shaft through an attachment means, such as a weld joint, a solder joint and a mechanical crimp; a temperature sensing means associated with the distal region; a handle associated with the proximal region; an electrical connector flexibly coupled to the handle; and at least one fluid delivery interface connection flexibly coupled to the handle for coupling a fluid delivery mechanism to deliver a treatment composition to the tissue.

0013Another aspect of the invention provides a method for delivering energy to a treatment area of an animal body comprising the steps of: providing a treatment system comprising a power source, a fluid delivery mechanism and an electrosurgical apparatus; coupling the power source to the electrosurgical apparatus through an electrical coupling means; coupling the fluid delivery mechanism to the electrosurgical apparatus through a fluid delivery interface connection; positioning the apparatus at or in the vicinity of the treatment area; administering the treatment composition from the fluid delivery mechanism to the animal body via the electrosurgical apparatus while maintaining the position of the apparatus within the body; delivering energy from the power source to the body via the electrosurgical apparatus while maintaining the position of the apparatus within the body; and monitoring temperature at a distal region of the apparatus. The aforementioned procedure may be completed with the electrical coupling means and the fluid delivery interface connection remaining coupled to the apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

0014These and other features of the embodiments of the invention will become more apparent in the following detailed description in which reference is made to the appended drawings wherein:

0015<figref idref="DRAWINGS">FIG. 1</figref> is a plan elevation view, fragmented, of a system incorporating an electrosurgical apparatus in accordance with a first embodiment of the present invention;

0016<figref idref="DRAWINGS">FIGS. 2A-2C</figref> are side elevation views of various embodiments of a distal region of an electrosurgical apparatus in accordance with the present invention;

0017<figref idref="DRAWINGS">FIG. 3</figref> is a side elevation view of a distal region of an electrosurgical apparatus in accordance with an alternate embodiment of the present invention;

0018<figref idref="DRAWINGS">FIGS. 4A-4B</figref> are plan elevation views of a distal region of an electrosurgical apparatus in accordance with two embodiments of the present invention comprising a stylet;

0019<figref idref="DRAWINGS">FIGS. 5A-5C</figref> are sectional side views through the shaft of various embodiments of the present invention comprising a stylet;

0020<figref idref="DRAWINGS">FIGS. 6A-6B</figref> are sectional side views through the shaft of two exemplary embodiments of the present invention, comprising a stylet and a thermocouple;

0021<figref idref="DRAWINGS">FIGS. 7A-7C</figref> are sectional front views through the shafts of various embodiments of an electrosurgical apparatus in accordance with the present invention;

0022<figref idref="DRAWINGS">FIG. 8</figref> is a sectional side view through the shaft of one embodiment of an electrosurgical apparatus in accordance with the present invention;

0023<figref idref="DRAWINGS">FIGS. 9A-9B</figref> are sectional top views through two embodiments of the handle of an electrosurgical apparatus in accordance with the present invention;

0024<figref idref="DRAWINGS">FIG. 10</figref> is a plan elevation view of an electrosurgical apparatus having a V-shaped handle in accordance with an alternate embodiment of the invention; and

0025<figref idref="DRAWINGS">FIGS. 11A-11B</figref> are first and second partial flowcharts of operations according to one embodiment of a method aspect of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

0026With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of certain embodiments of the present invention only, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice.

0027Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. In some instances, well-known structures and/or processes may not have been described or shown in detail to not obscure the invention. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting. Further, it is contemplated that the term animals as used herein includes, but is not limited to, humans.

0028Referring first to <figref idref="DRAWINGS">FIG. 1</figref>, an apparatus <b>102</b> in accordance with a first embodiment of the surgical apparatus aspect of the invention is shown in a system <b>100</b> for treating a body <b>104</b>. System <b>100</b> comprises the electrosurgical apparatus <b>102</b>; a power source control unit <b>106</b>; a return dispersive electrode <b>108</b>; and a fluid delivery mechanism <b>110</b>, such as, but not limited to, a syringe, for fluid composition injection. Power source control unit <b>106</b> may perform at least one of the following functions: supplying energy, for example RF energy, to apparatus <b>102</b>; measuring temperature feedback from at least one temperature sensor of apparatus <b>102</b>; and providing impedance measurement between a conductive region <b>112</b> of apparatus <b>102</b> and return dispersive electrode <b>108</b>. Impedance measurement may be used during placement to target a body tissue that has specific electrical properties. Apparatus <b>102</b> may comprise a conductive shaft <b>114</b> and a handle <b>116</b>. Conductive shaft <b>114</b> has an insulating coating <b>118</b> along a major portion of its outer surface, terminating adjacent exposed conductive region <b>112</b>. Conductive region <b>112</b> may be operable to transmit energy to a target area <b>120</b> of body <b>104</b>. In addition, conductive region <b>112</b> may aid in the penetration of apparatus <b>102</b> into body <b>104</b> and in the navigation of apparatus <b>102</b> to a desired target area <b>120</b>. It will therefore be understood by a person skilled in the art that conductive region <b>112</b> can be of varying dimensions and shapes and may be positioned at various locations on an apparatus <b>102</b> of the present invention. For example, conductive region <b>112</b> can be pointed, sharp, blunt, or open, varying in shape in accordance with the requirements of different procedures. Also, while the length of conductive region <b>112</b> in the first embodiment is between about 2 mm to about 10 mm, this length may vary depending on procedural requirements. Conductive region <b>112</b> may optionally be made of medical grade stainless steel, but other conductive biocompatible materials may be used as well.

0029In the first embodiment, shaft <b>114</b> and conductive region <b>112</b> are made from a conductive material, for example, stainless steel. Insulating coating <b>118</b> can be made of any type of insulating material, including but not limited to Polyethylene Terepthalate (PET), to prevent shaft <b>114</b> from delivering high frequency electrical current to tissue surrounding shaft <b>114</b>. This coating can be applied using dip coating, heat shrink coating or any other method that would be understood by a person skilled in the art.

0030Shaft <b>114</b> optionally has at least one aperture <b>122</b>, through which a treatment composition may exit from apparatus <b>102</b>. In one embodiment, illustrated in <figref idref="DRAWINGS">FIG. 2A</figref>, aperture <b>122</b> is defined by conductive shaft <b>114</b> at a side thereof, for example at or proximate conductive region <b>112</b>. The circumferential edge of aperture <b>122</b>, on the outer wall of shaft <b>114</b>, is optionally smooth to prevent cutting of tissue while apparatus <b>102</b> is inserted through body <b>104</b>. In embodiments where aperture <b>122</b> is located at or proximate conductive region <b>112</b>, aperture <b>122</b> beneficially allows fluid to be administered to body tissue <b>104</b> adjacent conductive region <b>112</b>. If the treatment composition is electrically conductive, its delivery may provide better conductivity from conductive region <b>112</b> to target area <b>120</b> surrounding conductive region <b>112</b> and greater efficacy of the energy delivered to body tissue <b>104</b>. A treatment composition may be delivered to a larger area of body tissue surrounding conductive region <b>112</b> by rotating apparatus <b>102</b> about the axis of conductive shaft <b>114</b> while simultaneously administering treatment composition through aperture <b>122</b>. Furthermore, as shown in <figref idref="DRAWINGS">FIG. 2B</figref>, more than one aperture <b>122</b> may be disposed circumferentially around shaft <b>114</b> in order to allow for substantially simultaneous delivery of a treatment composition to a larger region of tissue surrounding conductive region <b>112</b>. Alternatively or in addition, a treatment composition may be delivered to a specific region of tissue by rotating apparatus <b>102</b> about the axis of conductive shaft <b>114</b> to a desired orientation to target specific body tissue and subsequently administering treatment composition through aperture <b>122</b>. In other embodiments, aperture <b>122</b> may be located at a different region of shaft <b>114</b>, it may have various shapes and sizes and there may be more than one aperture <b>122</b>. An exemplary depiction of such an embodiment is shown in <figref idref="DRAWINGS">FIG. 2C</figref>.

0031Conductive shaft <b>114</b> of apparatus <b>102</b> may impart rigidity to apparatus <b>102</b> to facilitate the maneuvering of conductive region <b>112</b> to reach target area <b>120</b>, in which case shaft <b>114</b> may be referred to as being rigid or semi-rigid. In alternate embodiments, shaft <b>114</b> may be flexible. In the first embodiment of the invention, shaft <b>114</b> is hollow along its length, defining a lumen. Shaft <b>114</b> may be used to transmit a treatment composition to conductive region <b>112</b> and/or target area <b>120</b>, as well as to support and enclose any wiring associated with apparatus <b>102</b>. As well, an inner diameter of shaft <b>114</b> may be sufficiently dimensioned to accommodate a stylet or obturator in embodiments with an open tip, in addition to wiring for a temperature sensor associated with the distal end of shaft <b>114</b>. In some embodiments, intended for use in spinal procedures, the length of shaft <b>114</b> may vary between about 5 cm to about 15 cm. It is understood, however, that the length may vary beyond this range according to the procedure being performed.

0032In the first embodiment, handle <b>116</b> optionally comprises a flexible tube <b>124</b> coupled thereto in fluid communication with the lumen of shaft <b>114</b>. The flexibility of tube <b>124</b> may beneficially allow for greater maneuverability of apparatus <b>102</b>. A proximal end of flexible tube <b>124</b> may be coupled to a fluid delivery interface connection <b>126</b>. In other embodiments of the invention (not shown), handle <b>116</b> may not be necessary and flexible tube <b>124</b> may be coupled directly to shaft <b>114</b>. Handle <b>116</b> also optionally provides a grip <b>128</b> to allow a user to manipulate apparatus <b>102</b>. In one embodiment, handle <b>116</b> is manufactured from medical grade injection-moldable plastic or other material that can be sterilized using, for example, ethylene oxide. Handle <b>116</b> optionally has an aperture marker <b>130</b>, in line with aperture <b>122</b> along the axis of shaft <b>114</b>, to indicate the orientation of aperture <b>122</b> about the axis of shaft <b>114</b>. Aperture marker <b>130</b> allows the user to target tissue for the delivery of a treatment composition by indicating the orientation of aperture <b>122</b>. Handle <b>116</b> may further comprise orientation markings, including first orientation markings <b>132</b> to indicate, for example, 180° rotation of apparatus <b>102</b> about the axis of shaft <b>114</b> and second orientation markings <b>134</b> to indicate, for example, 90° rotation of apparatus <b>102</b> about the axis of shaft <b>114</b>. The user may refer to first and/or second orientation markings <b>132</b>,<b>134</b> to prevent apparatus <b>102</b> from rotating about the axis of shaft <b>114</b> while apparatus <b>102</b> is inserted through body tissue <b>104</b>, or to rotate apparatus <b>102</b> about the axis of shaft <b>114</b> to a desired orientation. First and second orientation markings <b>132</b>, <b>134</b> may be visual indicators, which may be flush with handle <b>116</b>, or tactile indicators, which may be textured or raised so that the user may see or feel markings <b>132</b>, <b>134</b> as apparatus <b>102</b> is inserted into body <b>104</b>. A proximal end of handle <b>116</b> optionally has a strain relief <b>136</b> with grip <b>128</b> running from the proximal end to the distal end of strain relief <b>136</b>. In the depicted embodiment, grip <b>128</b> is textured, for example with parallel ridges, to provide points of friction for the user while apparatus <b>102</b> is rotated about the axis of shaft <b>114</b> and inserted through body <b>104</b>. In this embodiment, the ridges on grip <b>128</b> may also be used to determine an angle of rotation of the apparatus. In one embodiment, strain relief <b>136</b> has a non-round (non-circular) cross-section, which may be square, triangular, or “toothed” like a mechanical gear. Strain relief <b>136</b> may be tapered with a larger distal outer diameter, in order to fit with handle <b>116</b>, and a smaller proximal outer diameter, in order to secure electrical cable <b>138</b> and flexible tubing <b>124</b>. This taper provides increased grip for the user and reduces slipping of the user's fingers as apparatus <b>102</b> is advanced into body <b>104</b>. Strain relief <b>136</b> may provide a comfortable handle for the user and may conform to a user's gripping preference. Strain relief <b>136</b> may be, for example, a soft flexible bend relief able to support electrical cable <b>138</b> and flexible tubing <b>124</b>. In the first embodiment shown in <figref idref="DRAWINGS">FIG. 1</figref>, electrical cable <b>138</b> and flexible tubing <b>124</b> extend from handle <b>116</b> and strain relief <b>136</b> in parallel and adjacent each other. Notably, in this embodiment, electrical cable <b>138</b> and flexible tubing <b>124</b> do not extend from handle <b>116</b> perpendicular to one another. This arrangement can provide a comfortable grasp and can enhance the ease of manipulation of apparatus <b>102</b> during placement, rotation, insertion, etc.

0033In the first embodiment, electrical energy may be supplied to conductive region <b>112</b> from power source control unit <b>106</b> via an electrical coupling, comprising electrical connector <b>140</b>, electrical cable <b>138</b> and conductive shaft <b>114</b>. All electrical contacts, except for conductive region <b>112</b>, may be isolated from the user by a connector pin housing located in electrical connector <b>140</b>. Electrical cable <b>138</b> may be flexible for flexibly coupling power source control unit <b>106</b> to conductive shaft <b>114</b>, which supplies energy to conductive region <b>112</b>. Electrical cable <b>138</b> may also relay temperature data back to power source control unit <b>106</b>. In the first embodiment of the invention, one conductor in electrical cable <b>138</b> acts as both a thermocouple wire as well as an RF delivery wire, as will be described in greater detail below. Utilizing a single conductor for both purposes reduces the overall mass of electrical cable <b>138</b> and minimizes the forces and moments applied at handle <b>116</b> during placement of apparatus <b>102</b> in body tissue <b>104</b>. It will be understood by a person skilled in the art that separate cables and/or conductors may alternatively be used in conjunction with a temperature sensor.

0034A fluid delivery mechanism <b>110</b> may be flexibly coupled to fluid delivery interface connection <b>126</b>, and through it to shaft <b>114</b> via flexible tubing <b>124</b>, in order to allow the administration of a treatment composition to a region of tissue in a patient's body. Therefore, as a benefit of the present invention, apparatus <b>102</b> may be simultaneously connected to fluid delivery mechanism <b>110</b> and power source control unit <b>106</b> in order to treat body <b>104</b>. Fluid delivery interface connection <b>126</b> may be any connector including, but not limited to, a luer type connector, that allows for the flow of fluid from fluid delivery mechanism <b>110</b> to flexible tubing <b>124</b>.

0035In operation of the first embodiment of the invention, apparatus <b>102</b> is inserted into body <b>104</b> and placed at target location <b>120</b>. Proper placement of apparatus <b>102</b> may be confirmed by applying electrical energy, such as RF energy, using conductive region <b>112</b> to stimulate target area <b>120</b>. An anesthetic fluid or another treatment composition can then be administered by actuating fluid delivery mechanism <b>110</b>. Apart from pharmacological agents, including anesthetics, the applied treatment composition can include, for example, a fluid that is electrically conductive, a fluid used to heat or cool the tissue or a fluid, such as a dye, that may be used to help visualize a treatment site. The treatment composition exits fluid delivery mechanism <b>110</b> and flows through fluid delivery interface connection <b>126</b>, flexible tube <b>124</b>, and the lumen of shaft <b>114</b> to conductive region <b>112</b> where it exits through aperture <b>122</b>. The incorporation of a fluid delivery system into apparatus <b>102</b>, as herein described, beneficially allows fluid delivery mechanism <b>110</b> to be pre-connected to fluid delivery interface connection <b>126</b>. Thus, the present invention helps to reduce the likelihood of inadvertent movement of conductive region <b>112</b> by removing the requirement to use and therefore remove a separate apparatus to apply a treatment composition, which would generally result in an adjustment of the position of conductive region <b>112</b>. Additionally, the use of flexible tube <b>124</b> further decreases the forces acting on handle <b>116</b> and shaft <b>114</b> when fluid delivery mechanism <b>110</b> is actuated to administer the treatment composition, for example, when a plunger on a syringe is depressed. Therefore, after stimulation to confirm proper placement of apparatus <b>102</b>, manual manipulation of apparatus <b>102</b> is minimized and thus the likelihood of shifting apparatus <b>102</b>, and thus conductive region <b>112</b>, out of position is decreased. In addition to, or in place of, electrical stimulation, other methods to confirm placement can also be used, such as measuring impedance or using imaging technologies, such as fluoroscopy. The use of an apparatus <b>102</b> with a shaft <b>114</b> whose distal end is sharp or pointed allows apparatus <b>102</b> to be inserted without the need to first insert a separate introducer tube or needle thus further reducing the likelihood of positional shifting of apparatus <b>102</b>. However, the use of an introducer is also envisioned and is considered to be within the scope of the invention.

0036After optionally administering the treatment composition, a high frequency, for example RF, electrical current may be applied to target area <b>120</b> through conductive region <b>112</b>. Return dispersive electrode <b>108</b> is provided to create a closed circuit when apparatus <b>102</b> is electrically operated in contact with body <b>104</b>. Notably, since fluid delivery mechanism <b>110</b> is still connected to apparatus <b>102</b> during energy delivery, further delivery of treatment composition coincident with the delivery of energy is possible. During treatment, temperature sensor feedback may be used to automatically control the RF energy delivered to body tissue <b>104</b> to help ensure safe operation of apparatus <b>102</b>. For example, if the body tissue temperature increases rapidly while applying RF energy as measured by the temperature sensor feedback mechanism, RF energy delivery to body tissue <b>104</b> may be suspended or reduced to provide a controlled ramp to the desired set temperature. In this manner, the user does not blindly apply RF energy to the body tissue, but is informed in real-time of the effects that RF energy delivery has on tissue temperature.

0037In some embodiments, as has been previously described, flexible tube <b>124</b> may provide the mechanical slack required to ensure that fluid delivery does not introduce added force to apparatus <b>102</b>. Other treatment tools, depending on the procedure, may also be flexibly connected to apparatus <b>102</b>. Apparatus <b>102</b> may therefore be provided with pre-formed connectors <b>142</b>, as shown in <figref idref="DRAWINGS">FIG. 1</figref>, for these treatment tools that are flexibly coupled to apparatus <b>102</b>.

0038In some embodiments of the invention, in order to facilitate precise placement of conductive region <b>112</b>, conductive region <b>112</b> is made distinguishable from the rest of apparatus <b>102</b> when viewed under x-ray fluoroscopy (or other radiographic imaging modalities) by providing a radiopaque marking at or adjacent the proximal end of conductive region <b>112</b> or at another location of shaft <b>114</b>. Alternatively, another form of marking, including, but not limited to, a magnetic or paramagnetic marking, may be provided, in order to visualize conductive region <b>112</b> using various medical imaging modalities such as MRI, ultrasound and CT.

0039Another embodiment of a shaft <b>114</b> of a surgical apparatus aspect of the invention can be seen in <figref idref="DRAWINGS">FIG. 3</figref>. This embodiment of shaft <b>114</b> comprises a textured surface <b>302</b>, a radiopaque marker <b>304</b>, and a curved conductive region <b>312</b>. Conductive region <b>312</b> defines an aperture <b>322</b> on the inside of curve <b>314</b> and a temperature sensor (not shown) at or proximate the distal end of conductive region <b>312</b>. Textured surface <b>302</b> allows for strong adhesion of insulating coating (not shown) to shaft <b>114</b> of apparatus <b>102</b> by increasing the shaft surface area. Radiopaque marker <b>304</b> provides visibility of the junction between curved conductive region <b>312</b> and insulated (or otherwise non-conductive) portions of shaft <b>114</b> under radiographic imaging. For example, radiopaque marker <b>304</b> may be placed so as to define the distal end point of the insulating coating (not shown) and the proximal start point of conductive region <b>312</b>. It should be understood by those skilled in the art that radiopaque marker <b>304</b> may include any arrangement or length of radiopaque marking(s) along shaft <b>114</b> of apparatus <b>102</b>. Other arrangements of radiopaque markings may include a series of equidistant markers to indicate insertion depth or may include radiopaque marking along the length of shaft <b>114</b>, optionally proximal to conductive region <b>312</b>. Equidistant depth markings may not necessarily be radiopaque, but may be colored to contrast with shaft <b>114</b> and to be visible to the user. Curved conductive region <b>312</b> provides added maneuverability of shaft <b>114</b> while it is advanced through body tissue <b>104</b>. Having aperture <b>322</b> oriented on the inside of curve <b>314</b> prevents the edge of aperture <b>322</b> from cutting body tissue as shaft <b>114</b> is advanced through body tissue <b>104</b>. However, aperture <b>322</b> may be positioned at various locations of shaft <b>114</b> and the invention is not limited in this regard. Furthermore, it should be noted that alternate embodiments of the present invention may comprise an apparatus having a curve without a textured surface or a textured surface without a curve. In addition, a curve may be present at other locations of shaft <b>114</b>. Further embodiments of the present invention may comprise a shape altering mechanism (or a shape actuator) in order to steer apparatus <b>102</b> within a patient's body. The shape actuator may include, but is not limited to, cables for a mechanical actuator, hydraulic or piezo-electric devices and solenoids.

0040As has been described with respect to the first embodiment of the present invention, shaft <b>114</b> may be sufficiently dimensioned so as to accommodate a stylet or obturating device. Enlarged top elevation views of two exemplary embodiments of the distal region of apparatus <b>102</b>, comprising a stylet <b>402</b>, are shown in <figref idref="DRAWINGS">FIG. 4</figref>. Referring first to <figref idref="DRAWINGS">FIG. 4A</figref>, shaft <b>114</b> defines a distal aperture <b>422</b> at a distal end <b>424</b> thereof and the lumen of shaft <b>114</b> contains stylet <b>402</b>, substantially occluding distal aperture <b>422</b> of shaft <b>114</b>; in such an embodiment, a distal end of stylet <b>402</b> has substantially the same shape as that of distal end <b>424</b> of shaft <b>114</b> and is flush with distal end <b>424</b>. Stylet <b>402</b> serves to discourage tissue from entering the lumen of shaft <b>114</b>. <figref idref="DRAWINGS">FIG. 4B</figref> shows an alternate embodiment whereby stylet <b>402</b> protrudes from the distal end <b>424</b> of shaft <b>114</b>. In further embodiments, only a portion of stylet <b>402</b> may protrude from distal end <b>424</b> of shaft <b>114</b>. Alternatively, stylet <b>402</b> may not completely occlude distal aperture <b>422</b>. For example, at least a portion of stylet <b>402</b> may be recessed inwards from the distal end <b>424</b> of shaft <b>114</b>. <figref idref="DRAWINGS">FIG. 5</figref> shows various embodiments of the disposition of stylet <b>402</b> within shaft <b>114</b>. In one embodiment, shown in <figref idref="DRAWINGS">FIG. 5A</figref>, stylet <b>402</b> may substantially fill the lumen defined by shaft <b>114</b>. Alternatively, stylet <b>402</b> may only partially fill the lumen, leaving a luminal space <b>502</b> between the exterior surface of a stylet shaft <b>504</b> and the interior surface of shaft <b>114</b>, as shown in <figref idref="DRAWINGS">FIG. 5B</figref>. Although <figref idref="DRAWINGS">FIG. 5B</figref> shows stylet shaft <b>504</b> extending along one side of shaft <b>114</b>, it should be understood that stylet shaft <b>504</b> can be located at any position within shaft <b>114</b>, for example near the center of shaft <b>114</b>. In a further embodiment, shown in <figref idref="DRAWINGS">FIG. 5C</figref>, stylet <b>402</b> is in the form of a cap or plug that occludes at least a portion of distal end <b>424</b> of shaft <b>114</b> and that may be affixed to the distal end of shaft <b>114</b>, for example by welding, but which does not extend through the length of shaft <b>114</b>.

0041Stylet <b>402</b> may be removable from shaft <b>114</b>, or may be affixed to shaft <b>114</b>, for example by welding, at one or more locations. Where stylet <b>402</b> is positioned such that a luminal space <b>502</b> is present, welding stylet <b>402</b> to shaft <b>114</b> can serve to reduce the radial and axial movement of stylet <b>402</b> within shaft <b>114</b>.

0042In one specific embodiment, stylet <b>402</b> may be made from a conductive material, such as stainless steel. In this embodiment, stylet <b>402</b> may be connected to shaft <b>114</b> or may be otherwise electrically coupled to shaft <b>114</b> and may thus be operable to deliver energy to a patient's body. Alternatively, stylet <b>402</b> may be independently connected to power source control unit <b>106</b>. If stylet <b>402</b> is conductive and is coupled to shaft <b>114</b> or power source control unit <b>106</b>, conductive region <b>112</b> may be defined as comprising the portions of shaft <b>114</b> and stylet <b>402</b> that deliver energy to target tissue area <b>120</b>.

0043<figref idref="DRAWINGS">FIG. 6</figref> shows two exemplary embodiments of a distal region of apparatus <b>102</b> comprising a temperature sensor <b>602</b>, aperture <b>122</b> and conductive region <b>112</b> (including the conductive regions of shaft <b>114</b> and stylet <b>402</b> where applicable, as described above). Temperature sensor <b>602</b> may be welded to the distal end of conductive region <b>112</b>, for example, either to shaft <b>114</b> or to stylet <b>402</b>. In some embodiments, as has been mentioned, temperature sensor <b>602</b> is a thermocouple, which may optionally include one or more thermocouple wires running in the lumen of shaft <b>114</b> and insulated from conductive shaft <b>114</b> and from any other conductive structure electrically coupled to shaft <b>114</b> or to power source control unit <b>106</b>. Insulation may include either insulation on the luminal surface (the surface facing the lumen through which the wire or wires run) of shaft <b>114</b> and other conductive structures, or insulation on the outer wall of the wire or wires.

0044The general use of a thermocouple to measure temperature is known in the art. However, in one embodiment, conductive region <b>112</b> may be a component of thermocouple <b>602</b>, as follows: the distal end of a thermocouple wire, made of a material that differs from the material of conductive region <b>112</b>, may be minimally stripped of insulation; temperature sensor <b>602</b> may then be formed by welding the distal end of the thermocouple wire to conductive region <b>112</b> of shaft <b>114</b> to create a thermocouple. Thus, shaft <b>114</b> and conductive region <b>112</b> may serve dual purposes, being utilized for energy delivery as well as forming a portion of temperature sensor <b>602</b>. In other embodiments, rather than forming a temperature sensor using conductive region <b>112</b>, as described above, a separate, self-contained temperature sensor may be attached to conductive region <b>112</b>. In any embodiment of the present invention, temperature sensor <b>602</b> need not comprise a thermocouple, and may comprise a thermistor, thermometer, optical temperature sensor or other temperature sensor. Furthermore, apparatus <b>102</b> may contain any number of temperature sensors, which may be positioned at a variety of locations along the side of the apparatus, not only at or near conductive region <b>112</b>, and which may protrude from, be flush with, or be recessed into the surface of conductive shaft <b>114</b>. In embodiments comprising a stylet <b>402</b> and a thermocouple <b>602</b>, stylet <b>402</b> may be a component of thermocouple <b>602</b>. In one such embodiment, illustrated in <figref idref="DRAWINGS">FIG. 6A</figref>, thermocouple junction <b>604</b> is formed by the welding of a wire <b>606</b> to stylet <b>402</b>. For example, if stylet <b>402</b> was made from stainless steel, a constantan (or any other wire made of a conductive material other than stainless steel) wire <b>606</b> might be used. In such an embodiment, stylet <b>402</b> may be welded or otherwise connected to shaft <b>114</b> at some other location of shaft <b>114</b>. In another embodiment, shown in <figref idref="DRAWINGS">FIG. 6B</figref>, stylet <b>402</b> may be made of one metal (for example, constantan) and shaft <b>114</b> may be made of a dissimilar metal (for example, stainless steel); stylet <b>402</b> may then be welded to shaft <b>114</b> in order to create a thermocouple junction <b>608</b>. In such an embodiment, a constantan wire (not shown) may extend from a proximal end of stylet shaft <b>504</b> in order to provide temperature information to power source control unit <b>106</b>. Although thermocouple junction <b>608</b> is shown at a tip of shaft <b>114</b>, other embodiments may have thermocouple junction <b>608</b> at an alternate location along shaft <b>114</b>. As has already been mentioned, more than one temperature sensor may be present on apparatus <b>102</b> and any temperature sensor may be a thermocouple, thermistor or other temperature sensing means.

0045In the first embodiment, the distal end of shaft <b>114</b> is sharpened in order to allow apparatus <b>102</b> to be inserted into body <b>104</b> without the use of an introducer tube or needle. Alternatively, in another embodiment, shaft <b>114</b> may not be sharpened, but stylet <b>402</b> may be sharpened or pointed and may protrude from shaft <b>114</b> in order achieve the same results as when shaft <b>114</b> is itself sharpened. As noted earlier, the circumferential edge of aperture <b>122</b>, on the outer surface of shaft <b>114</b>, is optionally smooth to prevent cutting of body tissue <b>104</b> while apparatus <b>102</b> is advanced therethrough. In some embodiments, stylet <b>402</b> may not completely occlude shaft <b>114</b>, allowing treatment composition to exit a distal end of shaft <b>114</b> if it is in communication with fluid delivery mechanism <b>110</b>. Thus, the term “aperture” as used herein is meant to include any opening in the body of shaft <b>114</b> and is not limited to a lateral aperture <b>122</b>.

0046While the term stylet is used to refer to structure <b>402</b> as shown in the various figures, this term is not intended to be exclusive, and is meant to include any obturator, trocar or other structure which, in embodiments with an open distal end, at least partially obstructs the distal end of shaft <b>114</b>, in order to, for example, prevent the passage of tissue into shaft <b>114</b>. The incorporation of a stylet into an apparatus of the present invention may be beneficial in that it may facilitate the incorporation of a temperature sensor <b>602</b> into apparatus <b>102</b> and make the process of manufacturing apparatus <b>102</b> more efficient.

0047Referring now to <figref idref="DRAWINGS">FIG. 7</figref>, sectional side views of a portion of conductive shaft <b>114</b> comprising insulating coating <b>118</b>, as illustrated in <figref idref="DRAWINGS">FIG. 1</figref>, are shown. In the embodiment shown in <figref idref="DRAWINGS">FIG. 7A</figref>, shaft <b>114</b> defines a lumen <b>702</b>, as has been described. Stylet shaft <b>504</b> and temperature measurement wire or wires <b>704</b> run through lumen <b>702</b>. In one embodiment, the present invention comprises a single wire <b>704</b> housed in lumen <b>702</b> of conductive shaft <b>114</b>, and welded to a dissimilar metal to form temperature sensor <b>602</b>. As mentioned above, the welding of wire <b>704</b> to a dissimilar metal may entail welding to shaft <b>114</b> or to stylet <b>402</b>. Alternatively, temperature wires <b>704</b> may comprise two or more wire components of a temperature sensor associated with apparatus <b>102</b>. Although <figref idref="DRAWINGS">FIGS. 7A and 7B</figref> show wire <b>704</b> and stylet shaft <b>504</b> (in <figref idref="DRAWINGS">FIG. 7A</figref>; in the embodiment shown in <figref idref="DRAWINGS">FIG. 7B</figref>, stylet shaft <b>504</b> is not present within lumen <b>702</b>) located substantially in the center of lumen <b>702</b> defined by shaft <b>114</b>, it should be clear that this is not intended to be limiting and that wire or wires <b>704</b> and/or stylet shaft <b>504</b> may be located at various positions within lumen <b>702</b>. Another embodiment of a shaft <b>114</b> of apparatus <b>102</b> is shown in <figref idref="DRAWINGS">FIG. 7C</figref>. This embodiment comprises a first lumen <b>706</b> and a second lumen <b>708</b>. Wiring <b>704</b> for temperature sensor <b>602</b> and conductive region <b>112</b> (in embodiments comprising such wiring) of apparatus <b>102</b> run through second lumen <b>708</b>, optionally contained within an insulating covering <b>710</b>. First lumen <b>706</b> may be beneficially used as a passage for the injection of a treatment composition. The size of lumen <b>706</b> and lumen <b>708</b> and the number of lumens required may vary depending on the embodiment. Another embodiment (not shown) comprises a plurality of lumens, for example as shown in <figref idref="DRAWINGS">FIG. 7C</figref>, as well as a stylet housed within one of the lumens.

0048Referring now to <figref idref="DRAWINGS">FIG. 8</figref>, a magnified sectional view of a portion of shaft <b>114</b>, according to one embodiment of the present invention, is shown. In this embodiment, thermocouple wiring <b>802</b> exits the lumen of conductive shaft <b>114</b> through a wiring aperture <b>804</b>. Wiring aperture <b>804</b> is optionally angled less than 90° with respect to the axis of conductive shaft <b>114</b>, as shown in <figref idref="DRAWINGS">FIG. 8</figref>, in order to minimize bending of wiring <b>802</b>. Use of this angle provides additional strain relief and protects the insulation of thermocouple wiring <b>802</b> as it exits shaft <b>114</b>, lies parallel to conductive shaft <b>114</b>, and is covered by insulating coating <b>118</b>. In alternate embodiments, any wires may exit shaft <b>114</b> at any angle. In yet further embodiments, all wires associated with apparatus <b>102</b> may remain within shaft <b>114</b> until a proximal end of shaft <b>114</b> is reached.

0049<figref idref="DRAWINGS">FIG. 9</figref> shows two magnified sectional top views (taken from a horizontal plane through apparatus <b>102</b>) of exemplary embodiments of handle <b>116</b>. Referring initially to the first embodiment, as depicted in <figref idref="DRAWINGS">FIG. 9A</figref>, handle <b>116</b> further comprises a compression gasket <b>902</b> to provide radial centering of shaft <b>114</b> in handle <b>116</b>. A crimp joint <b>904</b> provides electrical coupling between a first conductor <b>906</b> of electrical cable <b>138</b> and conductive shaft <b>114</b>. As described with reference to <figref idref="DRAWINGS">FIG. 1</figref>, first conductor <b>906</b> may beneficially be used both as a thermocouple wire as well as an RF delivery wire, as was mentioned with respect to the possible dual functionality of shaft <b>114</b> and conductive region <b>112</b>. In the embodiment shown, a second thermocouple wire <b>908</b> may be electrically coupled to a second conductor <b>910</b> of electrical cable <b>138</b> at solder joint <b>912</b>, and may enter conductive shaft <b>114</b> at a proximal end <b>914</b> of shaft <b>114</b>. Although elements <b>904</b> and <b>912</b> have been described as crimp and solder joints, respectively, other means of electrical coupling are envisioned for either element as well, including but not limited to soldering, mechanical crimping and welding. Flexible tube <b>124</b> is coupled to conductive shaft <b>114</b> at junction <b>916</b> and is slid over proximal end <b>914</b>. Junction <b>916</b> thus helps to provide fluid communication from fluid delivery mechanism <b>110</b> to aperture <b>122</b>.

0050In the embodiment shown in <figref idref="DRAWINGS">FIG. 9B</figref>, a solder joint <b>918</b> provides electrical coupling between a first conductor <b>906</b> of electrical cable <b>138</b> and conductive shaft <b>114</b>. In the embodiment shown, a second thermocouple wire <b>908</b> may be electrically coupled to a second conductor <b>910</b> of electrical cable <b>138</b> at solder joint <b>912</b> and may run along shaft <b>114</b> beneath insulating coating <b>118</b>. Although elements <b>918</b> and <b>912</b> have been described as solder joints, other means of electrical coupling are envisioned as well, including but not limited to mechanical crimping and welding.

0051Another embodiment of an apparatus aspect of the present invention is shown in <figref idref="DRAWINGS">FIG. 10</figref>. An apparatus <b>1000</b> has a handle <b>1002</b> configured to reduce torque. Handle <b>1002</b> incorporates a “V” shaped housing section <b>1004</b> having one arm for coupling to a treatment composition tube <b>1024</b> and a second arm for coupling to an electrical cable <b>1038</b>. Treatment composition tube <b>1024</b> and electrical cable <b>1038</b> extend from the end of handle <b>1002</b> and are coupled to fluid delivery interface connection <b>1026</b> and electrical connector <b>1040</b>, respectively, to substantially reduce the force transmitted to a conductive region <b>112</b>. Similar to apparatus <b>102</b>, apparatus <b>1000</b> in <figref idref="DRAWINGS">FIG. 10</figref> may also comprise a temperature sensor (not shown), an insulating coating <b>118</b>, an aperture <b>122</b>, first orientation markings <b>132</b> to indicate, for example, 180° rotation, second orientation markings <b>134</b> to indicate, for example, 90° rotation, and an aperture marker <b>130</b> to indicate a location of aperture <b>122</b>. It will be understood that the extent to which tube <b>1024</b> extends into handle <b>1002</b> or onto shaft <b>1024</b> can vary so long as it is in fluid communication with an aperture <b>122</b>.

0052Though not shown, another embodiment of a surgical apparatus aspect of this invention provides an apparatus comprising a shaft <b>114</b> and a conductive region <b>112</b> constructed from separate components. Shaft <b>114</b> could be made of a conductive material and then coated with an insulating material as in the embodiment shown in <figref idref="DRAWINGS">FIG. 1</figref> or could be made from a non-conductive material such as, but not restricted to, polyetheretherketone (PEEK). Conductive region <b>112</b> is made of a conductive material and attached to non-conductive shaft <b>114</b>. There are various methods in which conductive region <b>112</b> could be attached to non-conductive shaft <b>114</b> including, but not limited to, chemical bonding, press fits and screw fits. The wiring for temperature sensor <b>602</b> (in embodiments comprising a temperature sensor) and the conductive region (i.e. the wire or other means of transmitting electrical energy from a power source to the conductive region) may extend through and along a lumen of shaft <b>114</b> and connect to conductive region <b>112</b>. Alternately, in any of the embodiments of the present invention, the wiring for one or more of temperature sensor <b>602</b> and conductive region <b>112</b> may be extruded in the walls of shaft <b>114</b> such that the lumen could be used to deliver treatment composition but may not be required to house wiring.

0053Conductive region <b>112</b> can therefore serve multiple purposes. Conductive region <b>112</b> can be the site of passage for electric current to the surrounding tissue. It can also be the site for the release of a treatment composition. Finally, conductive region <b>112</b> can also house one or more temperature sensors <b>602</b>. Various tip geometries, such as a bevel on the end of the conductive region with a bottom hole and a mid-bevel temperature sensor are also contemplated embodiments (not shown). It should be understood that various other tip shapes and sizes; aperture sizes and placements, and temperature sensor placements are also considered to be viable options for this invention.

0054Referring to <figref idref="DRAWINGS">FIGS. 11A and 11B</figref>, a flowchart of operations <b>1100</b>, in accordance with one embodiment of a method aspect of the invention, is illustrated. At step <b>1102</b>, the method for using electrosurgical apparatus <b>102</b> is initiated. At step <b>1104</b>, an electrosurgical apparatus in accordance with the apparatus aspect of the present invention, is selected and obtained for performing the electrosurgical procedure. Reference to electrosurgical apparatus <b>102</b> of <figref idref="DRAWINGS">FIG. 1</figref> in connection with the method aspect of the invention is intended to be exemplary and illustrative only. Selection may thus include choosing one of an assortment of electrosurgical devices or apparatuses for appropriate dimension, such as length, tip shape, active tip length, gauge, etc. Selection may also include obtaining an electrosurgical device or apparatus from many devices or apparatuses and removing the one electrosurgical device or apparatus from packaging materials. At step <b>1106</b>, an electrosurgical system, such as system <b>100</b> in <figref idref="DRAWINGS">FIG. 1</figref>, is assembled. Assembly may include attachment of fluid delivery mechanism <b>110</b> and/or attachment of power source control unit <b>106</b>, as shown in <figref idref="DRAWINGS">FIG. 1</figref>. Assembly may also include the placement of return dispersive electrode <b>108</b> on body <b>104</b>. The order in which fluid delivery mechanism <b>110</b>, power source control unit <b>106</b> and return dispersive electrode <b>108</b>, are assembled, may vary with user preference. Partial assembly of electrosurgical system <b>100</b> is also possible; for example, the user may wish to place return dispersive electrode <b>108</b> and power source control unit <b>106</b>, but leave fluid delivery mechanism <b>110</b> detached from the system until a later step. Although a first embodiment of the method includes the attachment of power source control unit <b>106</b>, fluid delivery mechanism <b>110</b>, and return dispersive electrode <b>108</b>, it will be understood by those skilled in the art that variations in order of attachment may occur.

0055At step <b>1108</b>, the electrosurgical apparatus is positioned in body <b>104</b>. The step of positioning the electrosurgical apparatus may comprise a step of percutaneous insertion of the distal end of apparatus <b>102</b> into body <b>104</b>. The step of positioning may further comprise a step of utilizing an aid to precisely position the apparatus. For example, a visual, tactile or radiopaque marker may be used to help determine a location of the apparatus within body <b>104</b>. Visualization may involve the use of fluoroscopic, x-ray or other imaging. In addition, a user may monitor impedance of tissue as apparatus <b>102</b> is inserted through body <b>104</b> in order to position the apparatus within a desired tissue region. Alternatively, a user may deliver stimulation energy to body <b>104</b> in order to ascertain the proximity of apparatus <b>102</b> to various neural structures, thus facilitating the placement of apparatus <b>102</b> at a desired location within body <b>104</b>. In a first embodiment of a method aspect of the present invention, apparatus <b>102</b> is inserted to a final placement position in target area <b>120</b> of body <b>104</b>. However, positioning of apparatus <b>102</b> at any initial placement location may be performed at step <b>1108</b> and positioning of apparatus <b>102</b> in a final location may occur later, but before delivering energy at step <b>1114</b>.

0056At step <b>1110</b>, the user decides whether or not to administer a treatment composition to body <b>104</b>. The decision to administer treatment composition may include factors such as the preference of the physician, allergic reactions to treatment composition, and/or the delivery of nerve stimulation energy rather than nerve ablation energy. In the preferred embodiment, the user decides to administer treatment composition fluid and treatment composition fluid is administered via Yes branch to step <b>1112</b>. Administration of treatment composition fluid may include, but is not limited to, injection of sterile water or saline solution to modify electrical properties of a body tissue, injection of local anesthetic solution to block, hinder or change the signal propagation of pain from the body tissue and injection of a dye for visualization of the body tissue. It will be understood by those skilled in the art that other treatment fluids or combinations of the abovementioned treatment fluids may be injected into the body tissue surrounding a distal region of apparatus <b>102</b>. In step <b>1110</b>, if the user decides to not administer treatment composition fluid, the user chooses to deliver energy to the treatment area via No branch to step <b>1114</b>. Although this first embodiment of the method invention comprises the administration of treatment composition fluid at step <b>1112</b> prior to delivery of energy to treatment area at step <b>1114</b>, administration of treatment composition fluid may rather occur during and/or after delivery of energy to treatment area or may not occur at all.

0057While energy is being delivered to treatment area <b>120</b> at step <b>1114</b>, the user and/or power source control unit <b>106</b> monitors for completion of energy delivery to treatment area <b>120</b> at step <b>1116</b>. This monitoring may include, but is not limited to, user comparison of elapsed time while energy is being delivered to body tissue compared to the desired or set time for which delivery of energy to treatment area should occur, user choice to terminate energy delivery, logic in power source control unit <b>106</b> to end energy delivery upon detection of a system error during energy delivery, and/or measurement in power source control unit <b>106</b> to automatically terminate energy delivery upon elapsed time reaching desired treatment time, which is set on power source control unit <b>106</b>. System errors may include, but are not limited to, detection of discontinuity between electrosurgical apparatus <b>102</b> and power source control unit <b>106</b>, high or low impedance between conductive region <b>112</b> and return dispersive electrode <b>108</b> and delivered power exceeding power limit. Alternatively, energy delivery may be altered depending on feedback from temperature and/or impedance measurements, as described with respect to step <b>1120</b> below. If it is determined that energy delivery to the treatment area should be terminated, the procedure is stopped at step <b>1118</b> via the Yes branch. If energy delivery to the treatment area is not complete in step <b>1116</b>, measurements from electrosurgical apparatus <b>102</b> at treatment area <b>120</b> are monitored manually by the user or automatically by power source control unit <b>106</b> at step <b>1120</b> (<figref idref="DRAWINGS">FIG. 8B</figref>) via No branch from step <b>1116</b>.

0058In the first embodiment, temperature measurement of treatment area <b>120</b> is monitored at step <b>1120</b>. Monitoring of temperature in treatment area <b>120</b> may include, but is not limited to, the measurement of temperature through the use of a temperature sensor, such as a thermocouple or thermistor, feedback to power source control unit <b>106</b>, and temperature data display on a display or monitor, which may be separate from power source control unit <b>106</b>. In the first embodiment of the method invention, temperature of tissue in the treatment area is fed back to power source control unit <b>106</b> to be used for decision-making at step <b>1122</b>. At step <b>1122</b>, the measured temperature (or other measurement) of treatment area <b>120</b> is compared against predetermined values. These values may include value ranges, threshold values, individual values, etc. The user, who is continuously monitoring the temperature (or other measurement) of treatment area <b>120</b>, may make the comparison of measured temperature (or other measurement) against acceptable/unacceptable values. Alternatively, in the first embodiment, power source control unit <b>106</b> automatically compares the measured temperature (or other measurement) to predetermined values and makes a decision whether the measured temperature is acceptable or unacceptable. Notably at step <b>1120</b>, power source control unit <b>106</b> or the user may also monitor other measurements related to treatment area such as impedance, power, current and voltage, and use these measurements to make one or more decisions at step <b>1122</b>. If the measured temperature (and/or other measured parameters) is acceptable, energy delivery settings are not changed and energy delivery to treatment area continues via No branch back to step <b>1114</b>. If the measured temperature is unacceptable, treatment settings may be changed via Yes branch to step <b>1124</b>. At step <b>1124</b>, the user has the option to administer additional treatment composition fluid via fluid delivery mechanism <b>110</b>. This additional treatment composition may include, but is not limited to, any of the treatment compositions mentioned with respect to step <b>1112</b>. Administration of additional treatment composition fluid may occur at any time before, during, or after energy is being delivered to treatment area. Step <b>1124</b> may also be the initial delivery of treatment composition to treatment area if the user had decided to not administer treatment composition at step <b>1110</b>. If the user decides to administer treatment composition at step <b>1124</b>, additional treatment composition is administered to treatment area via Yes branch to step <b>1126</b>. With the completion of step <b>1126</b>, or if the user decides not to administer treatment composition at step <b>1124</b>, the user and/or power source control unit <b>106</b> has the option to modify system <b>100</b> settings to control energy being delivered to treatment area at step <b>1128</b>.

0059The option to modify system <b>100</b> settings, at step <b>1128</b>, may include, but is not limited to, a user choice to manually change power setting to increase/decrease temperature of treatment area <b>120</b>, a user choice to increase/decrease set temperature of system to change lesion size, and an automatic change in power setting to control temperature of treatment area <b>120</b>. At step <b>1128</b>, if the user and/or power source control unit <b>106</b> decide(s) not to modify system <b>100</b> settings to control energy being delivered, energy continues to be delivered to treatment area <b>120</b> via No branch at step <b>1114</b>. If the user decides to manually modify or change the system <b>100</b> settings to control energy being delivered to treatment area <b>120</b>, system settings are manually adjusted via Yes branch to step <b>1130</b>. Alternatively and in the first embodiment, if the power source control unit provides automatic control of energy delivery to treatment area and power source control unit <b>106</b> determines that system <b>100</b> parameter settings must be adjusted, adjustment occurs automatically via Yes branch to step <b>1130</b>. Automatic control may include the ability of power source control unit <b>106</b> to continuously monitor treatment measurements, compare said measurements to acceptable values, ranges, etc., make decisions based on said comparison and modify system parameter settings to obtain acceptable treatment measurements. System parameter settings may include, but are not limited to, settings for power, current, voltage, temperature, delivery rates and treatment time. Treatment measurements may include, but are not limited to, measurement of impedance, voltage, current, power, temperature, continuity between electrosurgical apparatus <b>102</b> and power source control unit and error checking. After all required adjustments are made, either manually by the user or automatically by power source control unit <b>106</b>, energy continues to be delivered to treatment area <b>120</b>, using the new settings, at step <b>1114</b>. The treatment procedure beneficially continues from step <b>1114</b> through to step <b>1130</b> until step <b>1118</b> is reached.

0060The embodiments of the invention described above are intended to be exemplary only. For example, although the invention has been described primarily utilizing RF or other high-frequency energy, other forms of energy may be used as well, including but not limited to thermal energy. The scope of the invention is therefore intended to be limited solely by the scope of the appended claims.

0061It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

0062Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims. All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention.